This chapter provides an overview of different methods for repeating objects in the Autodesk® Revit® Architecture software. We will also discuss tips, optimizations, and best practices to help keep your project files running smoothly.
In this chapter, you’ll learn to:
Revit Architecture offers several approaches to repeat geometry throughout your project. Some are better suited for specific conditions depending on your project, so we’ll provide an overview for each, along with key takeaways.
Component Families As outlined in Chapters 5 and 6, component families are best described as anything manufactured away from the job site and used throughout your project files. Component families are the core type of repeating object you will utilize. They can be constructed to be parametric by containing multiple types of the same family; think of one door with 10 types to represent variations in standard sizes. Component families can also be used with (and are a critical aspect of) groups, links, and assemblies.
The following are the key takeaways:
Groups Groups are collections of project objects such as system families, component families, or detail items. Model groups are collections of 3D geometries, whereas detail groups are strictly 2D. Groups are easily created by selecting the objects you want to include in the group and choosing Create Group on the ribbon. Creating a group will generate a single element that contains a collection of objects (which also makes it easy to move everything together). A good use case for groups is a condominium or apartment project. For typical units or apartments that will appear more than once in the project, you can select the objects and create a group. This group can then be copied or inserted at multiple project locations. Edit one group type, and all instances will update to match.
The following are the key takeaways:
Assemblies Assemblies are similar in many aspects to groups but with some unique tools directed toward construction workflows. Assemblies are collections of project objects similar to groups, organized in the Project Browser, along with any associated assembly views. To create an assembly, select the objects you want to include in the view, and choose Create Assembly on the ribbon.
The following are the key takeaways:
Revit Links Revit project files can be linked into one another. This is useful not only to divide large projects or campus buildings but also to repeat geometry. For example, your project may have identical wings or buildings on campus. The Revit project can be linked in and even allows for copies of the link to be created (all instances will update if reloaded). Links also have project-wide controls under Manage Links. Here you can reload, unload, or entirely remove the link from the host project.
The following are the key takeaways:
You can optimize your hardware in a number of ways to get the most out of your configuration. You should first look at the minimum hardware specifications for a computer running Revit Architecture. Autodesk has published those requirements on its website, and they are updated with each new release of the application. You can find the current specs at www.autodesk.com/revit; choose Features and then System Requirements under the Autodesk Revit Products page. Beyond the default specifications, you can do a number of things to help keep your files nimble. This section contains some additional recommendations.
You can use a rough formula to figure out how much memory you’re actually going to need for your project. The OS and other applications such as Microsoft Outlook will use some of your RAM, but you can predict how much RAM Revit Architecture will need to work effectively. The formula is as follows:
Let’s look at a couple of examples to demonstrate how this works. You have a project file with no linked files, and the file size on your server is 250 MB. So, 250 × 20 = 5,000 MB, or roughly 5 GB of RAM to operate.
In another example, you have a 300 MB file, a 100 MB structural model linked in, and four CAD files at 5 MB each.
(300 × 20) + (100 × 20) + (20 × 20) = 8,400 MB, or roughly 8.4 GB of RAM. For this example specifying at least 10–12 GB of RAM for the workstation would be recommended.
The one area where it can be difficult to predict, since each project file varies, is when upgrading a project. Upgrading a project is usually the most memory-intensive operation in Revit. Since it is a one-time operation (for each release), you can dedicate one workstation for this task. Specify one workstation with additional memory for upgrading, if you find it necessary.
The next area to improve model performance is to reduce your file size so you’re not using as much RAM. Here are some tips to do that and thereby improve your file speed:
Close your views. Close windows you’re not using to help minimize the drain on your resources. It’s easy to lose track of how many views are open, even if you’re concentrating on only a few views—and the more you open, the more information you will load into active RAM. If your main view is maximized, you can use the Close Hidden Windows tool to close all the windows but your active one; on the View tab, click the Close Hidden Windows button (it’s also conveniently located in the Quick Access toolbar). You can also assign this command to a keyboard shortcut such as XX.
Delete or remove unused CAD files. While working on a project you will often want to load content from another source to be used as a background. This could be a client’s CAD as-built drawings or a consultant’s mechanical, electrical, and plumbing (MEP) design. You might link or import these files into your drawing and forget about them during the busy course of the project. As you’ve seen from the earlier tips on RAM use, all these small files add up. Getting rid of them can speed up your file and is good housekeeping. If the file is linked, you can remove it using the Manage Links button from the Insert or Manage tab. Note that the Unload button does not remove it from the Revit Architecture project. If it is inserted, right-click an instance of the CAD file, and choose Select All Instances from the context menu. Clicking Delete will then remove all the instances in the view or project depending on your Select All Instances choice.
Link instead of importing CAD files. As a general rule, always link a CAD file rather than import it. You generally have greater control using a link than using imported geometry. The link can be removed or unloaded from the project and all views with a single action. A CAD link is similar to an Xref in Autodesk® AutoCAD® software and will update if the original CAD file is modified. An imported CAD file may be spread across several different views and is more difficult to hide or remove from specific views or the entire project. It also has no association to the original CAD file and will not subsequently update if modified outside the Revit project.
Turn on volume computation only as needed. Calculating the volumes on a large file can slow down your model speed immensely, especially when modifying bounding elements such as walls. Volume calculations are typically turned on when exporting to gbXML, but sometimes teams forget to turn them back off again. Volumes will recalculate each time you edit a room, move a wall, or change any of the building geometry. Turn off this option using the Area And Volume Computations dialog box found below the Room & Area panel on the Architecture tab (Figure 14.1).
Good file maintenance is critical to keeping your files running smoothly and your file sizes small. Here are some best practices and workflows identified in other areas of the book but consolidated in this section as a quick reference:
Model only what you need. Although it is possible to model to a very small level of detail, don’t fall into the trap of over-modeling. Be smart about what you choose to model and how much detail you show. If it’s not conveying information about the project, maybe it’s not needed. The amount of information you do or do not model should be based on your project size and complexity, your time frame, and your comfort level with the software.
When trying to decide how much detail to put into a model or even a family, you can use the following three very good rules of thumb to help you make the right decision for the element you’re looking to create:
Watch out for imported geometry. Although you have the ability to use geometry from several other file sources, use caution when doing so. Remember that everything you link into your model takes up about 20 times the file size in your system’s RAM. So, linking a 60 MB NURBS-based ceiling design will equal 1.2 GB of RAM and more than likely slow down your model. Deleting unused CAD files, using linking rather than importing, and cleaning up the CAD geometry before insertion will help keep problems to a minimum.
Utilize Purge Unused. You won’t use every family and every group you create in your model. The Purge Unused tool lets you get rid of those unused elements to help keep your file sizes at a reasonable level. This too can be found on the Manage tab on the Settings panel. If a file is very large, the tool can take several minutes to run, but eventually you’ll be presented with a list (Figure 14.3) of all the unused elements in your file.
In addition to all the things you can do to hone your Revit Architecture skills, you will begin to learn tips and shortcuts as your experience grows using the software. Here are some good tips to get you started:
Filter your selection. You can filter selection behavior by customizing any combination of links, underlay elements, pinned elements, the ability to select elements by face, and the ability to drag elements on selection. For example, on a large project, you may want to disable link selection to prevent accidental selection of linked models. These options can be toggled on the fly and are available in two locations: under the Modify arrow and on the lower-right corner of the status bar (Figure 14.4).
Customize your double-click behavior. If you navigate to Application Options User Interface Double-Click Options, you can customize the action for the element types (Figure 14.5). The available actions will vary based on the element type; however, each type has a Do Nothing option. For example, if you find yourself accidentally double-clicking to edit families, you can change the default behavior.
Make elevators visible in your plans. Suppose you want to create a shaft that will penetrate all the floors of your building and put an elevator in it that will show in all your plans. You could do this with an elevator family and cut a series of holes in the floors by editing floor profiles, but sometimes those holes stop aligning on their own recognizance. Fortunately, you can do both things at once using the Shaft tool on the Opening panel of the Architecture tab. Here, not only can you cut a vertical hole through multiple floors as a single object, but also you can insert 2D linework (using the Symbolic Line tool when editing the shaft opening sketch) to represent the elevator in plan view (Figure 14.6). Every time the shaft is cut, you’re certain to see the elevator linework.
Orient to view. Creating perspective views of isolated design elements can be quick and easy in plan view or in section view, but let’s say you want to see that same element in 3D to be able to work out the details.
Customize your shortcuts. To edit your keyboard shortcuts, choose Application Options. Choose the User Interface tab, and then click the Customize button. You can also access this command on the View tab in the ribbon under the User Interface flyout button. The Keyboard Shortcuts dialog box (Figure 14.7) allows you to edit those shortcuts. Consider making common shortcuts the same letter. One good example for this is the Visibility/Graphic Overrides dialog box, where both VV and VG are set by default as shortcuts (VV can be used for quicker access).
Copy a 3D view between projects. Suppose you made the perfect 3D view in your last project, and you can’t figure out how to get it into your current project. Fortunately, there’s a way to copy views from one project to another. Open both files in the same instance of Revit Architecture, and then do the following:
Disallow joining for walls. By default, Revit Architecture will join walls that intersect; however, you will eventually run into a condition where you need to override this behavior. First select a wall and hover over the Drag Wall End grip. Then right-click and choose Disallow Join. This will unjoin the wall and give you additional control to drag the wall end without it automatically jumping and joining to the intersecting wall.
Join geometry on parallel walls. If you have two parallel walls and there is an opening hosted on one wall (such as a door or window), you may want to automatically cut an opening through the second wall as well. If the walls are close enough, around 1′-0″ (300 mm) of each other, you can use the Join Geometry tool between the two walls. After that, an opening will be cut in the other parallel wall and move with the original family (Figure 14.8).
Prevent room numbers from shifting on cut/paste. By default, when you cut and paste rooms in a project, the room numbers will shift to the next available numbers. There is a trick to maintain the room numbers when cutting and pasting. Select the rooms you will be cutting to the Clipboard and create a group. Once the rooms are in a group, they can be cut and pasted without changing the room numbers. Then they can be ungrouped, and the group can be deleted from the Project Browser.
Copy objects from a Revit link. Need to copy an object from a Revit link and paste it into the host project? No problem; simply hover over the object in the link you want to copy and press the Tab key until the object is highlighted. Then click to select the object and use the standard copy and paste commands. The element will be copied from the link and pasted directly into the host project, where it can be directly manipulated (Figure 14.9).
Show annotation from a Revit link. Some annotation objects can be displayed from a Revit link. If the link contains annotation (such as room tags, dimensions, and so on) and you want to display it in the host project, set the Visibility/Graphic Overrides properties for the Revit link to By Linked View or Custom. You can further customize which view is displayed by adjusting the Linked View name on the Basics tab.
A number of resources are available to help you along the way and improve your use of the software, help you solve problems, and assist you in creating new content. There is a wealth of information online to help you learn or communicate with users far and wide. So, before you spend hours trying to solve a particularly challenging problem on your own, you might check some of these tools:
Revit Architecture Help Open the Revit Architecture Help by clicking the question-mark icon in the upper-right corner of the application. This tool will give you a basic synopsis of all the tools, buttons, and commands available in the application. It is available as a wiki at http://wikihelp.autodesk.com/Revit.
Subscription Support If you have purchased Revit Architecture on subscription, Revit Subscription Support offers web-based support. Its responses are speedy, its advice is top-notch, and chances are the support staff has seen your problem before. You can access Subscription Support at http://subscription.autodesk.com.
AUGI Autodesk User Group International (AUGI) is a source for tips and tricks as well as excellent user forums. The forums are free to participate in, and it’s a great place where you can ask questions, find answers, and discuss project workflows. AUGI is located at www.augi.com. Once you’re there, look for Revit Architecture.
Revit Forum Revit Forum is an ever-growing resource with forums and collections of blog posts and has many experienced Revit users regularly participating. Registration is free, and the forums are an extremely valuable resource for common issues and workflow recommendations. Revit Forum is located at www.revitforum.org.
YouTube Here’s a great reason to tell your IT department you need access to YouTube. Autodesk has its own channel with great free content: www.youtube.com/user/autodesk. It has hundreds of short videos showing how to perform specific tasks in Revit Architecture.
AECbytes AECbytes is a website dedicated to following the trends in the AEC industry, with a strong focus on BIM, technology, and the direction of the industry. The site is put together by Lachmi Khemlani; see www.aecbytes.com.
18.225.55.193